Cordero died on Sunday night after spending more than three months in hospital with the virus.
On Thursday, Braff shared an Instagram post explaining that he couldn’t sleep because he kept thinking Cordero might have caught Covid-19 from someone who wasn’t wearing a mask.
“I couldn’t fall asleep last night thinking that Nick may have gotten Covid from someone in New York City not wearing a mask who had it, but had no symptoms, so didn’t even know they had it,” he wrote beneath a photograph of Cordero and his one-year-old son, Elvis.
“Wearing a mask isn’t just for your own health; it’s for all the people who could get sick if you’re carrying it and don’t even know,” he continued.
“Somewhere out there, there is perchance a person who caused this tragedy and will never know.
“Anyway, that’s what kept me up. Nick loved being a Dad.”
Braff’s post comes after a GoFundMe page to support Cordero’s family raised more than $1m (£794,000).
Amanda Kloots, Cordero’s wife, shared a tribute to her husband on Instagram in the wake of his death: “God has another angel in heaven now,” she wrote beneath a black and white photograph of Cordero.
“My darling husband passed away this morning,” she added.
“He was surrounded in love by his family, singing and praying as he gently left this earth.”
Before his death, Cordero spent more than 90 days at Cedar-Sinai hospital fighting coronavirus and suffered multiple complications.
The actor underwent a leg amputation, received a temporary pacemaker and entered a medically-induced coma.
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